Pneumatic speina for velocipedes



(No Model.)

W. & D. D OIG. PNEUMATIC SPRING FOR VELOOIPEDBS.

Patented Sept. 14, 1897.

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UNITED STATES PATENT EEicE.

1VILLIAM DOIG AND DAVI D DOIG, OF LONDON, ENGLAND.

PNEUMATIC SPRIN G FORVELOCIPEDES.

SPECIFICATION forming part of Letters Patent No. 589,820, datedSeptember 14, 1897.

Application filed November 13,1896. Serial No. 611,958. (No model.)Patented in England July 31,1895 No. 1 1,551, and in France June 5,1896,1To. 256,976.

L 0 all 1071/0711, it may concern.-

Be it known that we, ILLIAM DOIG and DAVID DOIG", subjects of the Queenof Great Britain, residing at London, England, have invented certain newand useful Improvements in Pneumatic Springs for Velocipedes or otherRoad-Vehicles, (for which we have obtained Letters Patent of the UnitedKingdom of Great Britain and Ireland, No. let,55l, dated July 31, 1895,and Letters Patent of France, No. 256,976, dated June 5, 1896,) of whichthe following is a specification.

This invention relates to improvements in pneumatic springs forvelocipedes or other road-vehicles, whereby shock and vibrations causedby inequalities of the roadway are more or less absorbed or diminished.

The invention consists of one or more airtight and inflatable chambersplaced either directly between the axle or axles and the body of thevehicle or the rider or in any other equivalent position where itisrequired to reduce vibration.

In the further description of this invention reference is made to theaccompanying drawings, in which- Figure 1 is an elevation of thehandle-bar of a velocipede to which the improved spring is applied. Fig.2 is a side elevation of the same, and Fig. 3 is a section through theimproved air-tight chamber. Fig. at is an elevation of an air-tightchamber partially in-' closed in a spring-clip. Figs. 5 and 6 areelevations showing the air-chamber partially inclosed in a hinged metalframe, and Fig. 7 is a diagrammatic section of an air-chamber and itssurrounding parts.

The air-tight chamber or spring consists of a circumferential metalframe or clip a, in two or more parts with suitable means for connectingthe said parts. Leather side disks h are secured to or within the framea, and a metal washer c is attached to the center of each disk. A boltor stud (I, sometimes made square in section where it passes through thewashers, is provided with suitable means of attachment to the requiredparts of the vehicle. The stud d may pass entirely through theair-chamber, as in Figs. 1, 2, 3, and 5, or be in the form shown in Fig.7, separate on each side. An air-tight india-rubber bag 6,

having a valve f through which it may be inflated or deflated, is alsoprovided and is inclosed between the leather disks Z). The bag 6 is soformed and proportioned as to throw a considerable strain upon theleather disks when it is fully inflated, so that any strain communicatedto the leather disks is sustained by the air under compression withinthe bag. The bag 2 is sometimes made as an annular bag with a hole orcentral space through it for the passage of a stud d, as in Fig. 3, orwithout the central space, as in Fig. 7. It is convenient sometimes toattach metal rings g to the outer edges of the leather disks 1) as ameans of securing them within the metal frame a. This method isindicated in Fig. 7 5 but sometimes the disks are clamped to the frame aby screws, as indicated by Figs.

1 and In Figs. 1 and 2 the ainchamber is shown as placed between thehandle-bar h of a velocipede and a tubular extension 21 of the frame a,which is attached to the steeringhead in any suitable manner. In thiscase the handle-bar h is secured to the stud d by means of two side armsh, so that the leather disks 1), supported by the interior inflated bag6, cut off or diminish the vibration that would otherwise becommunicated from the steering-head through the tubular extensional Thusthere is no metallic connection between the metal point of support a(which is directly connected with 1'.) and the metal point of suspensiond, and it will be evident that the handle-bar h might be connecteddirectly to the frame a and the tubular extension 6 to the stud cl by afork with the same efiect and without departing from the nature of theinvention. Similarly a velocipede-saddle can be substituted for thehandle -bar h, thus avoiding much of the vibration now communicated tothe body of the rider. In this case the form and shape are modified asindicated by dotted line in Fig. 2, to permit the saddle to be kept aslow as may be required.

In Figs. 5 and 6 the metal point of support 2' is modified to suit itsposition on vehiclesas, for example, on the axles of vehicleswhile thebody of the vehicle (or its equivalent) would be mounted on the point ofsuspension (Z. It will be evident from this description that ourimproved air-chamber can be placed between two ordinary sets of metallicsprings-as, for example, at the j unction of the side and back springsof a hansom-cabone spring being attached to the point of support in anyconvenient manner and the other similarly to the point of suspension.

In Fig. 4 the frame a consists of a spring clip (semicircular intransverse section) with semicircular extensions 2 which when closedform a tube. This tubular extension may be arranged to embrace or to beinserted within another tube and be fixed in position or adapted foraxial movement, so that in the latter case its movement is guided in therequired direction. The diagrammatic section, Fig. 7, indicates aspring-clip frame a which in crosssec-tion is formed as a compound curveto inclose not only the metal rings 9 at the edges of the leather disks,but also shaped to give some additional support to the exterior of thedisks and to prevent undue transverse motion. By using a through-stud dof tubular form to act as a guide this object is further provided for ina similar manner to that already mentioned for the tubular extension 2While avoiding continuous metal contacts throughout. Therectangular-shaped frame a in Figs. 5 and 6 is provided with ahingejoint a and suitable means for fastening the halves of the frametogether, as indicated in the figures.

It is to be understood that while we believe the materials named are thebest for our purpose we do not restrict ourselves to the use of thematerials herein specified, as others may be found sufficient for thepurposes in 1 many forms of road-vehicles, and that the positions ofsuspension and support are reversible.

lVhat We claim, and desire to secure by Letters Patent of the UnitedStates, is

1. In a pneumatic spring for velocipedes or other road-vehicles, thecombination of a circumferential frame a in two or more parts connectedtogether; leather side disks 1), 5. having their circumferential edgessecured to the said frame; metal washers c, c, secured to the centralportions of the said disks, a stud or studs (Z on which the said washersare mounted; and an inflatable air-tight bag a. placed within the saidframe and adapted to distend the said leather disks when inflated.substantially as and for the purpose set forth.

2. In a pneumatic spring for velocipedes or other road-vehicles, thecombination of t spring-clip circumferential frame a semicircular incross-section and having extensions.

@ leather side disks 1), I), having metal rings g at theircircumferential edges; metal Washers c, c, secured to the centralwashers of the said disks, a stud or studs don which the said washersare mounted; and an inflatable airtight bag 6, placed within the saidframe and adapted to distend the said leather disks when inflated,substantially as and for the purpose set forth.

In testimony whereof we have signed this specification in the presenceof two subscribing witnesses.

IVILLIAM DOIG. DAVID DOIG. \Vitnesses:

M. E. CARRINGTON, CHAS. Roman.

